EP 0751408 B1 19981202 - A method of sintering glass preforms for manufacturing planar optical waveguides
Title (en)
A method of sintering glass preforms for manufacturing planar optical waveguides
Title (de)
Verfahren zum Sintern von Glasvorformen für die Herstellung von planären optischen Wellenleitern
Title (fr)
Procédé de frittage de préformes en verre pour la fabrication de guides d'ondes optiques planars
Publication
Application
Priority
US 49626895 A 19950628
Abstract (en)
[origin: EP0751408A1] A planar waveguide structure is produced by a process comprising sintering substantially pure SiO2 layers in a He2/BCl3 or He2/BF3 atmosphere. This results in the generation of a liquid phase of substantially lower viscosity than that of the deposited silica by itself. Since viscous sintering is enhanced by the presence of this liquid, consolidation occurs at lower temperature, e.g. 1000-1100 DEG C, than those used in the prior art, e.g. 1350-1500 DEG C. Much of the B2O3 remains unreacted with the silica particles it helps to sinter, acting like a flux to bring about consolidation. This remaining B2O3 is removed at the conclusion of the consolidation procedure by steam treatment at temperatures of 900 DEG C - 1100 DEG C. Some boron is incorporated into the silica layer, changing its Coefficient of Thermal Expansion (CTE) without substantially increasing its index. Thus, this method improves both structure and processing of planar waveguides by reducing the processing temperature and producing a glass which does not bow the substrate and essentially eliminates birefringence resulting in polarization dependent losses. This greatly benefits sophisticated circuits such as those intended for wavelength diversion multiplexing and allows narrow and precisely positional pass bands.
IPC 1-7
IPC 8 full level
G02B 6/13 (2006.01); C03B 8/04 (2006.01); C03B 19/14 (2006.01); C03B 20/00 (2006.01); C03C 17/02 (2006.01); G02B 6/132 (2006.01); G02B 6/12 (2006.01)
CPC (source: EP KR US)
C03B 19/1453 (2013.01 - EP US); C03C 17/02 (2013.01 - EP US); G02B 6/132 (2013.01 - EP US); G02F 1/0102 (2013.01 - KR); G02F 1/035 (2013.01 - KR); C03B 2201/10 (2013.01 - EP US); G02B 2006/12038 (2013.01 - EP US); G02B 2006/12064 (2013.01 - EP US); G02B 2006/12116 (2013.01 - EP US)
Designated contracting state (EPC)
DE DK FR GB IT NL SE
DOCDB simple family (publication)
EP 0751408 A1 19970102; EP 0751408 B1 19981202; CN 1159590 A 19970917; DE 69601054 D1 19990114; DE 69601054 T2 19990610; DK 0751408 T3 19990816; JP 3262259 B2 20020304; JP H0921921 A 19970121; KR 970002393 A 19970124; SG 46740 A1 19980220; TW 369611 B 19990911; US 5800860 A 19980901
DOCDB simple family (application)
EP 96304513 A 19960618; CN 96108600 A 19960619; DE 69601054 T 19960618; DK 96304513 T 19960618; JP 16873596 A 19960628; KR 19960024566 A 19960627; SG 1996010154 A 19960625; TW 85104688 A 19960419; US 49626895 A 19950628